渦輪增壓器
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渦輪增壓器是一種壓縮器，它可以從一個流體能量補充能量到另一個流體上。通常是工業上為了恢復原有的動能與熱能，然而渦輪增壓器時常使用於內燃機引擎製造出的原本要排放的廢氣中，利用廢氣的熱量來壓縮引擎內的空氣。而被壓縮的空氣藉由增加氧氣在內燃機的量而增加輸出的力量。與超級增壓一樣，渦輪增壓器雖增加內燃機的重量，但是引擎的力量也增加，不過由於渦輪增壓器把廢熱回收，所以要求的燃料比超級增壓還少。
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[编辑] 運作原理
A turbocharger is a dynamic gas compressor or liquid pump, in which a fluid from one stream is pumped, and in the case of a gas compressed, by the mechanical action of an impeller which is powered by a turbine that recovers energy from another fluid stream.
In almost all cases the impeller and turbine are mounted on ends of a single shaft passing through a center hub rotating assembly (CHRA) between the impeller and turbine. The CHRA contains bearings for the shaft and may also contain systems for lubrication and cooling.
[编辑] 引擎內部的燃燒
渦輪增壓器常使用於增加內燃機的進氣量，進而增加馬力輸出量。在飛航應用上渦輪增壓器是為了能在高海拔的地方能夠有自然進氣引擎在低海拔的進氣量，通常稱之增壓正常化(turbonormalizer)。 軸、軸承、輪葉與渦輪會以數萬到數十萬RPM運轉。許多種軸承在如此高的轉速需要潤滑與冷卻系統。渦輪增壓器的潤滑系統可以是獨立系統或是從引擎供油系統提供。提供潤滑系統的冷卻器可能為雙重冷卻系統，冷卻劑可以是外來的，如引擎冷卻系統，或是空冷機組。通常汽車上渦輪增壓器的潤滑與冷卻水系統是來自於機油與引擎冷卻液。有些特殊的軸承，像是箔軸承，能夠減少或不需額外潤滑且降低冷卻系統的門檻。
CHRA的對面是渦輪機與輪葉，包含在它們折疊起來像是蝸牛殼的錐形風罩內。這些風罩是在收集與導風流的方向。而這個風罩的形狀與大小可以很直接的影響渦輪增壓器的整體特性與性能。圓錐管道的每一處截面積(A), 和該處與風罩中心所成的半徑(R) , 可以表示成一個比值(AR，A/R，A:R)。通常基本的渦輪增壓器擁有多種AR值的渦輪風罩可供選擇。這樣便可允許設計者對整個動力系統去對性能、反應度與效率去做協調。
以相當高的速度旋轉的壓縮渦輪機會吸引大量的空氣推進引擎內。當渦輪增壓機的輸出流量超過引擎體積流量，進氣系統就會出現氣壓。而組件旋轉的速度是與壓縮空氣總質量的氣流成比例。自從渦輪增壓器的轉速遠超過機械所需，或是為了安全起見，轉速必需要可以被控制住。廢氣門是最常見的機械式轉速控制系統，通常也會另外增加壓力控制器(boost controller)來輔助。廢氣門的主要功能是當進氣壓達到設定的上限，一部分的廢氣就會繞過渦輪機，就會達到定氣壓的效果。
渦輪增壓器能夠提高輸出引擎效率，但是需要解決它的主要限制才能推廣。汽車的自然進氣向下衝程引擎為了吸取空氣進去汽缸，只使用一個活塞創造一個低壓區。從空氣量與燃料分子決定有多少位能能夠在燃燒的時候對活塞去使多少的力，因為大氣是恆壓的，最後進氣量會被限制住。利用這個能力把空氣吸入燃燒室內的多寡稱之容積效率(volumetric efficiency)。從渦輪增壓器增加了空氣進入汽缸的壓力，與該空氣量進入到汽缸內很大程度上取決於時間與壓力，氣體吸引造成壓力增加。吸收的壓力大小，在缺乏渦輪增壓器之下是決定於大氣壓力，但是加入渦輪增壓器之後增加的壓力就能控制。
利用壓縮機增加進氣缸的氣壓通常稱為強制進氣(forced induction)。 離心式超級增壓器的運作方式與渦輪增壓器相同；然而，讓壓縮機的旋轉能量前者是引擎曲軸而後者是廢氣。因此渦輪增壓原則上是比較有效率的，因為渦輪的動力來自引擎的熱能，把廢氣的能量轉化成動能，不然就浪費掉能量了。超級增壓器的使用，是在犧牲一部分引擎產生的能量，產生了淨增產值的能量。
[编辑] 燃油效率
渦輪增壓器雖讓引擎增加可觀的馬力輸出，但是引擎也產生更多的廢熱。當車子本身設計無法承受高熱環境，把渦輪增壓器裝進去可能會是一個難題。額外的廢熱加上增壓器提供較低的壓縮比(擴張比)稍微有助於較低的熱效率，但是卻直接影響整體的燃油效率。 還有另種稱為主管冷卻型的冷卻法會很大的影響到燃料效率。即使intercooling是有幫助的，但是燃燒室內的總壓縮比還是比自然進氣引擎還大。當引擎釋放出最大能量時避免爆震出現，通常為了冷卻目的會實現產生額外的燃料花費。當這seems counterintuitive，這部份的燃油不會燃燒。換句話說，燃油在液體霧化成氣霧時把熱量吸走了。而且，氮是燃燒室內相對密度高的物質，所以氮氣能夠承受比較高的熱量。氮氣把持住這個熱量直到經由廢氣排出來避免破壞性的爆震。這使設計者經由犧牲燃油經濟性取得燃油泵內較好的熱力性能輸出功率。要完整燃燒汽油，最理想的空氣/燃油比(A/F)是14.7:1。通常一部擁有渦輪增壓引擎車在最大的boost的A/F值大約是12:1。設計系統時，較多混合物的汽油在運轉時有時會有瑕疵，像是觸媒轉化器不能在太高的溫度下運作，或是引擎有太高的壓縮比而無法與供油系統有效運作。 最後，高效率的渦輪增壓器也會對自身影響到燃油效率。使用較小的渦輪增壓器在中低轉速上會提供比較快的回應與較低的延遲(lag)，但是會堵塞引擎的排氣部位與轉速提升時產生巨大的熱量。比較大的渦輪增壓器在高RPM的時候是相當有效率，但是在正常行駛時這樣並不實際。可變式輪葉與滾珠軸承技術能使渦輪增壓器在更大的運作範圍內更有效率的運轉，然而，不少汽車使用這類技術會產生額外的問題(參閱可變式幾何渦輪增壓器(Variable geometry turbocharger))。目前使用這種渦輪增壓器的汽油車只有Porsche 911 (997) Turbo。目前只有連續式雙渦輪增壓器(sequential turbocharging)才能提供全面性的輸出優勢，因為它在低轉速時用小渦輪，而高轉速時用大渦輪。 大多數現今的汽車的引擎管理系統(engine management systems)能夠根據當時溫度、燃料品質、海拔高度及其他因素控制歧管壓力與燃油運輸。有些系統則是先進到能夠提供更精確的燃料燃燒品質。像是Saab的Trionic-7 system使用電子式指示提供燃燒上更優秀的回應性。 Volkswagen/Audi的新2.0升FSI渦輪引擎結合了傾斜點火與直接噴射技術能在低負荷狀態保有推進力在低負荷狀態。這個系統是非常複雜到包含許多移動性的零件與感應器去維持氣室的氣流特性，能夠使用分層指示來提供更優秀的霧化。直接噴射系統同時擁有巨大影響，使發動機具有更佳的冷卻效果，就能夠使用較典型的氣門式渦輪噴射引擎更高的壓縮比。
[编辑] 汽車設計原理
根據理想氣體方程式，當其他變因保持不變，假設系統內部壓力增加，溫度會隨之提升。那使用渦輪增壓器會存在負面結果，原因是空氣被壓縮機壓縮而造成進入引擎之前空氣溫度就已經提升。 渦輪的轉速視旋轉部份的大小、重量、進氣歧管的氣壓及壓縮機的設計，通常快到80,000至200,000 RPM(慣性較低的可達150,000-250,000 RPM)。在這麼高的轉速之下，滾珠軸承將會產生問題，所以大多的渦輪增壓器使用液態軸承。此軸承的特色是有一流動式的油層能夠懸浮與冷卻移動式零件。這層油通常是來自於引擎機油循環系統。有些渦輪增壓器使用不可置信精確的滾珠軸承來提供比液態軸承更少摩擦，因此這種軸承是懸浮斥水性的洞裡。更少摩擦表示渦輪軸可以用較輕的材質製成，減少所謂的渦輪延遲(turbo lag或boost lag)。有些設計人員使用水冷式渦輪增壓器要藉此提高軸承壽命。
開發使用箔軸承的渦輪增壓器是為了排除使用軸承冷卻與供油系統，藉此排除大多數已知的失敗，也意味能夠降低延遲。
要維持氣壓恆定，渦輪增壓器裡多餘的廢氣氣流會經由廢氣閥(wastegate)調節，使得這些氣流不會經過渦輪。這樣便能調節渦輪的旋轉速度，進而調整壓縮機的輸出能力。廢氣閥的開啟時機是由渦輪產生的壓縮空氣來決定，並可以藉著螺線管去控制壓力施予廢氣閥薄膜的強度。螺線管可以被自動性能管理系統(Automatic Performance Control)、引擎的電子控制單位(electronic control unit，ECU)或是微電腦壓力控制器。另一種提高增壓的方法是透過利用排氣閥隨時檢查壓力並且放掉氣門去維持薄膜承受的壓力且低於系統的壓力。 部分的渦輪增壓器(通常稱為可變式幾何渦輪增壓器)利用一組葉片在廢氣槽(exhaust housing)去維持定量氣體快速經過渦輪，這種控制機制也用於發電機的汽輪機。這些渦輪增壓器的延遲很小，擁有很小的氣壓臨界值(1500 rpm即可達到最大增壓)，而且轉速高的引擎上出現的效率也不差；這些增壓器也用於柴油引擎。[1]這些引擎大多都沒有廢氣閥。這些葉片是被與廢氣閥相同的薄膜控制，但是控制的等級需求是不太相同的。
第一部使用這種渦輪增壓器的汽車是1989年份限量版的Shelby CSX-VNT，採用2.2L的汽油引擎。Shelby CSX-VNT利用一顆Garrett的VNT-25型渦輪，因為它使用與Garrett T-25相同的壓縮機和軸。這一渦輪機通常稱之可變式噴嘴渦輪增壓器(VNT)。渦輪增壓器的製造商 Aerocharger使用名為’可變區域渦輪噴嘴’(Variable Area Turbine Nozzle，VATN)來詮釋這種渦輪噴嘴。另外常見的說法包括’可變渦輪截面’(Variable Turbine Geometry，VTG)、’可變渦輪幾何增壓器’(Variable Geometry Turbo，VGT)與’可變配氣相位’(Variable Vane Turbine，VVT)。Chrysler公司在1990年有一批汽車使用這種渦輪增壓器，包含Dodge Daytona 與 Dodge Shadow。這些引擎能夠產生174匹馬力與225磅-呎的扭力，與正常的引擎相比，它使用正常的冷卻系統，產生出來相同的馬力但增加25磅-呎的扭力與比較快的反應(較少的延遲)。然而，不包含VATN或VNT的Turbo III引擎能夠產生224匹馬力。目前不知道為何Chrysler不繼續使用VGT渦輪增壓引擎，最有可能的原因是市場需要Chrysler設計的V6引擎更甚於VGT引擎。[2]
2006年的Porsche 911 Turbo有3.6L直列六缸雙渦輪增壓引擎，而渦輪是使用BorgWarner的可變幾何渦輪系統(VGTs)。這顯然因為雖然在柴油引擎與Shelby CSX-VNT上VGT系統採用了一段時間，但是這是自從1989-90的1250顆Dodge引擎以外的第一次在汽油車使用這種技術。有些人抱怨使用此系統的汽油車廢氣溫度比使用柴油引擎高不少，而這對敏感的可動式渦輪葉片會有不利的影響。而且這個裝置也比其他的渦輪增壓器還要昂貴。Porsche的工程師聲稱新的911 Turbo已經解決這些問題。
還有一種叫做離心式渦輪，運行時有時像正常渦輪，有時像超級增壓。由於它是皮帶驅動式(沒有使用廢氣)，所以沒有任何延遲， 然而它的臨界壓力與一般的渦輪相比並不自然。它的代價是產生多餘的拖曳力在曲軸上，使得效率降低。優點是沒有延遲，也易於安裝 – 不須改裝廢氣路線，而且易於保養。
[编辑] 可靠性
渦輪增壓器可能會被髒的或是無效的機油加速耗損，而且大多的製造商建議要給渦輪增壓引擎勤加換油；許多擁有者及一些公司建議使用合成機油，與傳統機油相比，他比較易於流動而且比較不容易壞掉。因為渦輪增壓器運轉時容易發熱，很多人建議在熄火前如果渦輪增壓器才剛運轉完畢，讓引擎待命1至3分鐘(多數的製造商指出在熄火前待機10秒來確定渦輪增壓器確實運行於它的待機速度，來避免因機油停止供給造成軸承損壞)。這樣可讓渦輪吸入較低的排氣溫度來降溫，而且能夠保證當渦輪與排氣歧管溫度依然非常高時機油有輸送到渦輪增壓器，否則潤滑油的煤焦會再軸承吸收油時卡在機器內，導致當汽車重新啟動時軸承很快的耗損與失效。高溫機油內的雜質會累積起來並導致堵塞供油系統。這問題在柴油引擎上並不明顯，因為柴油引擎的廢棄溫較低與引擎轉速相對比較低。
渦輪計時器(turbo timer)可以讓運轉中的引擎提供一個已預先指定的時間來自動的提供降溫週期。箔軸承內的煤焦也能除去。更複雜的是使用水冷式軸承卡夾需要防止煤焦跑進去。當引擎關閉和自然的熱循環會使卡夾內的水沸騰。所以還是不要在渦輪還在運轉時把引擎關閉。
依照慣例是使用管狀頂蓋而不是使用鑄鐵的歧管，這樣會因為較輕的頂蓋而減少冷卻所需的時間。
[编辑] 延遲
延遲現象有時會使駕駛者感覺在踏下油門與渦輪提供出衝力之間有一段時間差。這個問題是由於當時排氣系統推動渦輪的壓力需要克服渦輪的旋轉慣性與要提供歧管壓力的最低轉速。而超級增壓器不會出現這個現象。(離心式超級增壓器並不會在低轉速時產生歧管壓力，就像是超級增壓器的現象)。相反的在轉速低的狀況之下渦輪增壓器提供較少的壓力且引擎比裝載超級增壓器的引擎還要有效率。
延遲現象可以由降低渦輪零件的慣性而減少，像是使用較輕的材質來使渦輪比較易於轉動。陶瓷渦輪在這裡是很好的解決之道。但相對的在產生最大壓力的時候是比其他材料脆弱。Another way to reduce lag is to change the aspect ratio of the turbine by reducing the diameter and increasing the gas-flow path-length. Increasing the upper-deck air pressure and improving the wastegate response helps but there are cost increases and reliability disadvantages that car manufacturers are not happy about. Lag is also reduced by using a foil bearing rather than a conventional oil bearing. This reduces friction and contributes to faster acceleration of the turbo's rotating assembly. Variable-nozzle turbochargers (discussed above) also reduce lag.
Another common method of equalizing turbo lag is to have the turbine wheel "clipped", or to reduce the surface area of the turbine wheel's rotating blades. By clipping a minute portion off the tip of each blade of the turbine wheel, less restriction is imposed upon the escaping exhaust gases. This imparts less impedance onto the flow of exhaust gases at low RPM, allowing the vehicle to retain more of its low-end torque, but also pushes the effective boost RPM to a slightly higher level. The amount a turbine wheel is and can be clipped is highly application-specific. Turbine clipping is measured and specified in degrees.
Other setups, most notably in V-type engines, utilize two identically-sized but smaller turbos, each fed by a separate set of exhaust streams from the engine. The two smaller turbos produce the same (or more) aggregate amount of boost as a larger single turbo, but since they are smaller they reach their optimal RPM, and thus optimal boost delivery, faster. Such an arrangement of turbos is typically referred to as a parallel twin-turbo system.
Some car makers combat lag by using two small turbos (such as Kia, Toyota, Subaru, Maserati, Mazda, and Audi). A typical arrangement for this is to have one turbo active across the entire rev range of the engine and one coming on-line at higher RPM. Early designs would have one turbocharger active up to a certain RPM, after which both turbochargers are active. Below this RPM, both exhaust and air inlet of the secondary turbo are closed. Being individually smaller they do not suffer from excessive lag and having the second turbo operating at a higher RPM range allows it to get to full rotational speed before it is required. Such combinations are referred to as a sequential twin-turbo. Sequential twin-turbos are usually much more complicated than a single or parallel twin-turbo systems because they require what amounts to three sets of pipes-intake and wastegate pipes for the two turbochargers as well as valves to control the direction of the exhaust gases. An example of this is the current BMW E60 5-Series 535d. Another well-known example is the 1993-2002 Mazda RX-7. Many new diesel engines use this technology to not only eliminate lag but also to reduce fuel consumption and produce cleaner emissions.
Lag is not to be confused with the boost threshold; however, many publications still make this basic mistake. The boost threshold of a turbo system describes the minimum turbo RPM at which the turbo is physically able to supply the requested boost level [來源請求]. Newer turbocharger and engine developments have caused boost thresholds to steadily decline to where day-to-day use feels perfectly natural. Putting your foot down at 1200 engine RPM and having no boost until 2000 engine RPM is an example of boost threshold and not lag.
Electrical boosting ("E-boosting") is a new technology under development; it uses a high speed electrical motor to drive the turbocharger to speed before exhaust gases are available, e.g. from a stop-light. The electric motor is about an inch long. [3]
Race cars often utilise an Anti-Lag System to completely eliminate lag at the cost of reduced turbocharger life.
On modern diesel engines, this problem is virtually eliminated by utilising a variable geometry turbocharger.
[编辑] 歧管壓力(Boost)
Boost refers to the increase in manifold pressure that is generated by the turbocharger in the intake path or specifically intake manifold that exceeds normal atmospheric pressure. This is also the level of boost as shown on a pressure gauge, usually in bar, psi or possibly kPa This is representative of the extra air pressure that is achieved over what would be achieved without the forced induction. Manifold pressure should not be confused with the amount, or "weight" of air that a turbo can flow.
Boost pressure is limited to keep the entire engine system including the turbo inside its design operating range by controlling the wastegate which shunts the exhaust gases away from the exhaust side turbine. In some cars the maximum boost depends on the fuel's octane rating and is electronically regulated using a knock sensor, see Automatic Performance Control (APC).
Many diesel engines do not have any wastegate because the amount of exhaust energy is controlled directly by the amount of fuel injected into the engine and slight variations in boost pressure do not make a difference for the engine. 链接标题
[编辑] 應用於汽車上
Turbocharging is very common on diesel engines in conventional automobiles, in trucks, locomotives, for marine and heavy machinery applications. In fact, for current automotive applications, non-turbocharged diesel engines are becoming increasingly rare. Diesels are particularly suitable for turbocharging for several reasons:
- Naturally-aspirated diesels have lower power-to-weight ratios compared to gasoline engines; turbocharging will improve this P:W ratio.
- Diesel engines require more robust construction because they already run at very high compression ratio and at high temperatures so they generally require little additional reinforcement to be able to cope with the addition of the turbocharger. Gasoline engines often require extensive modification for turbocharging.
- Diesel engines have a narrower band of engine speeds at which they operate, thus making the operating characteristics of the turbocharger over that "rev range" less of a compromise than on a gasoline-powered engine.
- Diesel engines blow nothing but air into the cylinders during cylinder charging, squirting fuel into the cylinder only after the intake valve has closed and compression has begun. Gasoline/petrol engines differ from this in that both fuel and air are introduced during the intake cycle and both are compressed during the compression cycle. The higher intake charge temperatures of forced-induction engines reduces the amount of compression that is possible with a gasoline/petrol engine, whereas diesel engines are far less sensitive to this.
Today, turbocharging is most commonly used on two types of engines: Gasoline engines in high-performance automobiles and diesel engines in transportation and other industrial equipment. Small cars in particular benefit from this technology, as there is often little room to fit a larger-output (and physically larger) engine. Saab is a leader in production car turbochargers, starting with the 1978 Saab 99; all current Saab models are turbocharged with the exception of the 9-7X. The Porsche 944 utilized a turbo unit in the 944 Turbo (Porsche internal model number 951), to great advantage, bringing its 0-100 km/h (0-60 mph) times very close to its contemporary non-turbo "big brother", the Porsche 928.
Chrysler Corporation was an innovator of turbocharger use in the 1980s. Many of their production vehicles, for example the Chrysler LeBaron, Dodge Daytona, Dodge Shadow/Plymouth Sundance twins, and the Dodge Spirit/Plymouth Acclaim twins were available with turbochargers, and they proved very popular with the public. They are still considered competitive vehicles today, and the experience Chrysler obtained in observing turbochargers in real-world conditions has allowed them to further turbocharger technology with the PT Cruiser Turbo, the Dodge SRT-4 and the Dodge Caliber SRT-4.
Small car turbos are increasingly being used as the basis for small jet engines used for flying model aircraft—though the conversion is a highly specialised job—one not without its dangers. Jet engine enthusiasts have constructed home-built jet engines from automotive turbochargers, often running on propane and using a home-built combustion canister plumbed in between the high pressure side of the turbo's compressor and the intake side of the turbine. An oil supply for the bearings is still needed, usually provided by an electric pump. Starting such home-built jets is usually achieved by blowing air through the unit with a compressor or a domestic leaf-blower. Making these engines is not an easy task- unless the combustion canister design is correct the engine will either fail to start, fail to stabilise once running or even over-rev and destroy itself.
Most modern turbocharged aircraft use an adjustable wastegate. The wastegate is controlled manually, or by a pneumatic/hydraulic control system, or, as is becoming more and more common, by a flight computer. In the interests of engine longevity, the wastegate is usually kept open, or nearly so, at sea-level to keep from overboosting the engine. As the aircraft climbs, the wastegate is gradually closed, maintaining the manifold pressure at or above sea-level. In aftermarket applications, aircraft turbochargers sometimes do not overboost the engine, but rather compress ambient air to sea-level pressure. For this reason, such aircraft are sometimes referred to as being turbo-normalised. Most applications produced by the major manufacturers (Beech, Cessna, Piper and others) increase the maximum engine intake air pressure by as much as 35%. Special attention to engine cooling and component strength is required because of the increased combustion heat and power.
Turbo-Alternator is a form of turbocharger that generates electricity instead of boosting engine's air flow. On September 21 2005, Foresight Vehicle announced the first known implementation of such unit for automobiles, under the name TIGERS (Turbo-generator Integrated Gas Energy Recovery System).
[编辑] 實行
The most common implemenations of a turbocharger involve mounting the unit to the downpipe of a vehicle under the hood towards the firewall of the vehicle. Centrifugal turbos must connect to the accessory belt of the vehicle.
A rear mount implementation is used when there is insufficient engine bay room; it may be used in place of the stock muffler. The turbo returns the boosted air (which is pulled in from a filter mounted somewhere in the rear) to the front of the vehicle and optionally through an intercooler, and then to the intake of the engine. Wiring and oil lines must be run to the rear of the vehicle and an auxilary oil pump must be used to return oil from the turbo to the engine. According to Horsepower TV (2/3/2007), you can expect a loss of 1 psi using a rear mount turbo, because of loss due to the long pipe routings, and also about a 100ºF drop in intake air temperature. The decrease is due to the cooler exhaust gases (thus a cooler turbo unit) and the cooler intermediate pipe between the turbo and the intake. Benefits include easier maintenance, because the unit is more accessible.
[编辑] 歷史
The turbocharger was invented by Swiss engineer Alfred Buchi, who had been working on steam turbines. His patent for the internal combustion turbocharger was applied for in 1905. Diesel ships and locomotives with turbochargers began appearing in the 1920s.
One of the first applications of a turbocharger to a non-Diesel engine came when General Electric engineer, Sanford Moss attached a turbo to a V12 Liberty aircraft engine. The engine was tested at Pikes Peak in Colorado at 14,000 feet to demonstrate that it could eliminate the power losses usually experienced in internal combustion engines as a result of altitude.
Turbochargers were first used in production aircraft engines in the 1930s prior to World War II. The primary purpose behind most aircraft-based applications was to increase the altitude at which the airplane can fly, by compensating for the lower atmospheric pressure present at high altitude. Aircraft such as the Lockheed P-38 Lightning, Boeing B-17 Flying Fortress and B-29 Superfortress all used exhaust driven "turbo-superchargers" to increase high altitude engine power. It is important to note that turbosupercharged aircraft engines actually utilized a gear-driven centrifugal type supercharger in series with a turbocharger.
Turbo-Diesel trucks were produced in Europe and America (notably by Cummins) after 1949. The turbocharger hit the automobile world in 1952 when Fred Agabashian qualified for pole position at the Indianapolis 500 and led for 100 miles before tire shards disabled the blower.
The first production turbocharged automobile engines came from General Motors. The A-body Oldsmobile Cutlass Jetfire and Chevrolet Corvair Monza Spyder were both fitted with turbochargers in 1962. The Oldsmobile is often recognized as the first, since it came out a few months earlier than the Corvair. Its Turbo Jetfire was a 215 in³ (3.5 L) V8, while the Corvair engine was either a 145 in³ (2.3 L)(1962-63) or a 164 in³ (2.7 L) (1964-66) flat-6. Both of these engines were abandoned within a few years, and GM's next turbo engine came more than ten years later.
Offenhauser's turbocharged engines returned to Indianapolis in 1966, with victories coming in 1968. The Offy turbo peaked at over 1,000 hp in 1973, while Porsche dominated the Can-Am series with a 1100 hp 917/30. Turbocharged cars dominated the Le Mans between 1976 and 1994.
BMW led the resurgence of the automobile turbo with the 1973 2002 Turbo, with Porsche following with the 911 Turbo, introduced at the 1974 Paris Motor Show. Buick was the first GM division to bring back the turbo, in the 1978 Buick Regal, followed by the Mercedes-Benz 300D and Saab 99 in 1978. The worlds first production turbodiesel automobile was also introduced in 1978 by Peugeot with the launch of the Peugeot 604 turbodiesel. Today, nearly all automotive diesels are turbocharged.
Alfa Romeo introduced first Italian (mass produced) turbocharged car Alfetta GTV 2000 Turbodelta in 1979, Pontiac also introduced a turbo in 1980 and Volvo Cars followed in 1981. Renault however gave another step and installed a turbocharger to the smallest and lightest car they had, the R5, making it the first Supermini automobile with a turbocharger in year 1980. This gave the car about 160bhp in street form and up to 300+ in race setup, an exorbitant power for a 1400cc motor. When combined with its incredible lightweight chassis, it could nip at the heels of the incredibly fast Ferrari 308.
In Formula One, in the so called "Turbo Era" of Template:F1 until Template:F1, engines with a capacity of 1500 cc could achieve anywhere from 1000 to 1500 hp (746 to 1119 kW) (Renault, Honda, BMW). Renault was the first manufacturer to apply turbo technology in the F1 field, in 1977. The project's high cost was compensated for by its performance, and led to other engine manufacturers following suit. The Turbo-charged engines took over the F1 field and ended the Ford Cosworth DFV era in the mid 1980s. However, the FIA decided that turbos were making the sport too dangerous and expensive, and from Template:F1 onwards, the maximum boost pressure was reduced before the technology was banned completely for Template:F1.
In Rallying, turbocharged engines of up to 2000cc have long been the preferred motive power for the Group A/World Rally Car (top level) competitors, due to the exceptional power-to-weight ratios (and enormous torque) attainable. This combines with the use of vehicles with relatively small bodyshells for manoeuvreability and handling. As turbo outputs rose to similar levels as the F1 category (see above), the FIA, rather than banning the technology, enforced a restricted turbo inlet diameter (currently 34mm), effectively "starving" the turbo of compressible air and making high boost pressures unfeasible. The success of small, turbocharged, four-wheel-drive vehicles in rally competition, beginning with the Audi Quattro, has led to exceptional road cars in the modern era such as the Lancia Delta Integrale, Toyota Celica GT-Four, Subaru Impreza WRX and the Mitsubishi Lancer Evolution.
Although late to use turbocharging, Chrysler Corporation turned to turbochargers in 1984 and quickly churned out more turbocharged engines than any other manufacturer, using turbocharged, fuel-injected 2.2 and 2.5 liter four-cylinder engines in minivans, sedans, and coupes. Their 2.2 liter turbocharged engines ranged from 142 hp to 225 hp, a substantial gain over the normally aspirated ratings of 86 to 93 horsepower; the 2.5 liter engines had about 150 horsepower and had no intercooler. Though the company stopped using turbochargers in 1993, they returned to turbocharged engines in 2002 with their 2.4 liter engines, boosting output by 70 horsepower. [4]
[编辑] 參照
- Don Sherman (February 2006). "Happy 100th Birthday to the Turbocharger". Automobile Magazine.
- ↑ Parkhurst·Terry - Turbochargers: an interview with Garrett’s Martin Verschoor Allpar, LLC - 於12 December 2006zh-tw:造;zh-cn:采訪。
- ↑ Allpar turbo engine history
- ↑ Parkhurst·Terry - Turbochargers: an interview with Garrett’s Martin Verschoor Allpar, LLC - 於12/12/2006zh-tw:造;zh-cn:采訪。
- ↑ Chrysler turbocharged engines (Allpar)
[编辑] 相關條目
- Boost gauge
- Boost controller
- Twin-turbo
- Intercooler
- Turbo timer
- Supercharger
- Blow off valve
- Forced Induction
